【摘要】 对带有颗粒阻尼的简支梁系统的动力学特性进行了研究。文中首先通过实验方法对未加颗粒阻尼和添加颗粒阻尼的简支梁加速度幅频响应进行对比,发现颗粒阻尼能够有效地抑制系统共振峰值,降低系统共振频率的特点;在基础做简谐振动情况下,得到颗粒体对系统产生的冲击力受约化加速度控制会经历一系列倍周期分岔的规律,给出了分岔周期冲击力的谐波分量表达式;最后,推导出含颗粒阻尼单自由度系统在简谐激励作用下稳态响应的计算公式。更多还原

【Abstract】 The dynamic characteristics of Nopd (non obstructive particle damping) attached to a vertical forced vibration system are investigated. Some typical Nopd effects on the system are shown by comparing FRFs of simply supported beams with and without Nopd. It is observed that the impact force between granular bed and container bottom, controlled by normalized vibration acceleration, undergoes a series of double periods bifurcations. A unified expression is derived for all of the impact force with different periods bifurcations. The continuous beam attached with Nopd is simplified to an equivalent s.d.o.f system, and an exact response solution for the steady-state motion of the system under harmonic excitation is provided.更多还原